TALLAHASSEE, Fla. -- Lawmakers in the state House on Thursday criticized a Senate plan to change the way Florida's multibillion-dollar public school budget is adjusted to send millions more each year to the six districts that have a higher cost of living.

Senate President Jim King, R-Jacksonville, wants the formula revamped -- and the issue has emerged as the key to lawmakers both reaching a deal on the $57 billion spending plan for the fiscal year that begins July 1 and ending the session on time next week.

The Senate change would mean less money for 27 counties, but would hit the state's two most populous counties, Miami-Dade and Broward, particularly hard. Next year alone, Miami-Dade would lose nearly $28 million and Broward another $8 million.

Palm Beach, Pinellas, Monroe and Collier are the other counties currently getting the adjustment and stand to lose some money in the Senate plan. House members criticized the study cited by the Senate as the rationale for its proposed change.

"I ask that you recognize this study for what it is: An economic proposal that has no basis in fact," said Rep. Joe Pickens, R-Palatka.

Lawmakers are still hopeful the budget deal could be hammered out by early next week, which would give the House and Senate enough time to vote on the compromise proposal and finish their work by the session's scheduled April 30 end.

Meanwhile, the state's top budget-writers continued swapping offers Thursday on other funding issues. Senate Appropriations Chairman Ken Pruitt, R-Port St. Lucie, and House Appropriations Chairman Bruce Kyle, R-Fort Myers are still trying to bridge many gaps, including health care spending.

"We just don't have enough money," Pruitt said. "These cuts in nursing homes and hospitals are tough. It's just finding common ground."

The cost-of-living formula change backed by the Senate, which would be phased in over three years, adds a wage factor into the formula. That is designed to account for quality-of-life "amenities" like beaches, weather and nightlife that might attract teachers and other workers to an area despite a higher cost of living.

"You can't go to Publix and buy your food with the sunshine and the sand," said Rep. Nan Rich, D-Weston.

The House took no vote Thursday, but many lawmakers urged Speaker Johnnie Byrd, R-Plant City, to stick with their chamber's original plan (CS-HB 745). Under that proposal, funding would be raised for the 61 districts that currently lose money under the formula, and no district would take a huge budget hit.

The House debated the issue for about four hours, after which Byrd told the chamber he would "engage in advocacy on behalf of the House position." He urged lawmakers to do the same with their Senate counterparts.

Rep. David Simmons, the top education budget-writer in the House, called the Senate plan unacceptable. And Rep. Shelley Vana, D-Lantana, said the fight over the formula was distracting lawmakers from the more critical question of how much is spent on schools.

"What we're doing to education is unconscionable," she said. "It is not providing an adequate education to our children."

The final numbers won't be available until the formula question is settled. But, in general, public schools will get a modest increase in the neighborhood of 4.5 percent per student next fiscal year.

That's comparable to the growth of the current budget and, as school boards move ahead on class-size reduction, means there won't be much money left to boost teacher salaries or pay soaring insurance premiums.